Presentation on theme: "WATER RESOURCES MANAGEMENT IN OMAN Dr. Aisha M. Al-Qurashi Surface water Expert Directorate General of Water Resources Assessment Sultanate of Oman Ministry."— Presentation transcript:
WATER RESOURCES MANAGEMENT IN OMAN Dr. Aisha M. Al-Qurashi Surface water Expert Directorate General of Water Resources Assessment Sultanate of Oman Ministry of Regional Municipalities & Water Resources
Geographical Location Oman is located at the southeast tip of the Arabian Peninsula lying on the Arabian Sea and the Sea of Oman. Oman covers a total area of approximately 309,500 km 2. The coastline extends for 3,165 km in length. The land area is composed of varying topographic features: valleys and desert account for 82% of the land mass; mountain ranges, 15%; and the coastal plains, 3%.
Climate and Hydrology The Climate in the Sultanate of Oman varies from region to another and from one season to another but can be divided mainly into two seasons, namely: Winter: It begins in November and last until April. Average temperatures are mild and pleasant, ranging between ( C) in Muscat Governorate and varies slightly in other regions. In this season the country is affected by thermal cycles which cause rainfall in the eastern parts of the Sultanate. Summer: it extends from May to October, and temperature average ranges between ( C) in Muscat Governorate, varying slightly in other regions. During this season, the tropical climate moves to the north towards the Arabian Peninsula, and the southwest monsoon affects the far south of the country and the south-east. Dhofar Region can be regarded as the exception, as it has a strong monsoon climate and receives warm winds from the Indian Ocean
Rainfall Distribution in Oman
There are four major ecosystems causing rain in the Sultanate, which can be summarized as follows: High air pressure caused by cold boundaries: It is common during winter and early spring, where it leads to rain fairly constant in the northern parts of the country, and scattered showers of rain in the central and south of the country. Tropical cyclones from the Arabian Sea : The thick cyclones originate over the Arabian Sea and reach the Sultanate in an average of five years in Dhofar and ten years in Muscat, and lead to heavy rains on the southern and eastern shores of the Sultanate during the months of May and December. Seasonal coastal currents: These currents are common during the period from June to September, associated with surface currents over the Arabian Sea, where these currents are dominated by the south-west current, and may be mixed partly with air current coming from the Gulf of Aden. As a result, the summer in the Governorate of Dhofar is characterized by high humidity, a decrease in the level of evaporation and fog during the months of June and July. Convectional Rainfall : This kind of rain is the result of the presence of local convectional storms, which can occur at any time during the year. Precipitation continued…
Evapotranspiration The high summer temperatures and low humidity in the interior region allow high evaporation conditions. Daily evapotranspiration average exceeds 12 mm, while it drops in the coastal areas of Al Batinah and Salalah to reach less than 10 mm per day, as a result of high humidity. Climate and Hydrology, Continued …
Available Water Resources 1. Conventional Water Resources (represents 84%) and can be divided into : Surface water resources: –Rainfall: the total average annual amount of rainfall is estimated at about 9,481 Million m 3. About 80% of this quantity (7,585 Million m3) is lost to evaporation. –Wadi Flows: During floods significant quantities of water (1,422 Million m 3 ) replenishes the shallow alluvial aquifer through direct recharge along the coarse wadi gravel and the gradual release of water from recharge dams. The remaining (474 Million m 3 ) is lost to the sea. –Ghaili aflaj: which are based on the perennial flow in a wadi. These type of aflaj represent 48% of the total number of aflaj in the Sultanate. –Springs: Most of these springs are located in the mountainous areas. Springs on the northern side of the mountains discharge hot water and are used for therapeutic purposes
Conventional Water Resources, continued… Groundwater resources: –Represents 94% of the available conventional water resources and can provide about (1,295 Million m 3 /year) of water. –It is the most important source of available water in Oman and usually used through dug wells and Daoudi aflaj. –The geological characteristics of Oman regions play an important role in forming groundwater resources; therefore it differs in quality and quantity from a region to another. –exists in renewable alluvial aquifers (unconfined and shallow) recharged from infiltration of surface water flow along wadis. –The non renewable groundwater resources are found in relatively deep confined aquifers which receive little or no recharge.
Available water Resources Use of Non-Conventional Water resources It represents 6% and can be divided into : Desalination of Seawater and Brackish Water Wastewater Treatment and Reuse Treatment and Reuse of Oil Production Water Cloud seeding
Use of Non-Conventional Water resources
Water Use in Oman During the last ten years, the Sultanate witnessed a great transformation in water uses. Consumption of water for industrial, commercial, municipal and tourism increased by 300% times than normal rate from (86 Million m 3 ) in 1998 to (399 Million m 3 ) in The increase is attributed to the growing economic activities in all sectors in that period. The agricultural sector is the main consumer of water with a consumption of about 78% followed by the domestic uses (12%), the commercial, industrial and municipal uses (6%), the environmental uses (3%) and livestock (1%).
Water Deficit Available data indicate that the quantities of consumed water exceeds the available resources by about (378 Million m 3 ) per year.
Water Resources Supply Management These was carried out through: –Water Resources Monitoring –Water Resources Exploration and Assessment –Water Resources Development
Water Supply Management 1- Water Resources Monitoring SalinityRain Stations Sum Fala j Wel l Well drainag e lagoon s Springs Afla j Well measurement s Automatic dam s Flo w peak Wadi planet s Region AlBatina South AlBatina North Musanda m AlBuraimi AlDhahira AlDakhili a AlShariya North AlSharqia South AlWusta AlNajd Salalah Sum
Water Supply Management 2- Water Resources Exploration and Assessment Water resources exploration and assessment programs have been implemented in various areas and governorates of the Sultanate during the past decades. These programs led to the discovery of a number of groundwater aquifers which allowed the implementation of water supply schemes, the most important of which are: Al Masarrat Project Ash'Sharqiah Project Wadi Al Maawil Project Project of Wadi Rawnab in Al Wusta Region Al Najd
Water Supply Management 3- Water Resources Development The Government of the Sultanate of Oman is exerting great efforts to develop water resources in order to meet the increasing water demands resulting from the successful, economical, industrial and social development the various fields. Several programs related to water resources development have been implemented among these: Dams: - Recharge Dams: The main purpose of these dams is to enhance groundwater storage through getting use of valleys flood water which is often wasted in sea and desert. The number of recharge dams that have been constructed during the period from are (39). - Flood Protection Dams: There are (14) dams are being constructed in Muscat and Musandam Governorate to protect occupants of downstream areas from flood risks and can be used for recharge when ever possible. Rainwater harvesting: –Small retention dams –Cisterns –Quarry pits
Water Resources Development Rainwater Harvesting in Jabal Al-Akhdar In order to solve the problems related to water shortage, the Government studied the implementation of several techniques, among them is the rain water harvesting. Jabal Al-Ahdar is one of the mountainous remote area that located in Northern Oman. It is a unique area and known for its spectaculars scenery and it comprises an important historical heritage and cultural treasures. Even though, the mean annual rainfall is about 300 mm which is higher than other parts in Oman, the areas suffers from natural water resources. The rugged terrain with steep mountain slopes which can retain little rainfall water and the bigger part infiltrates into rock fractures or it drains off directly to the foothills where it reaches the aquifers of the adjoining plains.
Rainwater Harvesting in Jabal Al-Akhdar Water Situation in Jabal Al-Akhdar Water is supplied by aflaj which are fed by springs or underground mother wells Currently, the water demand is rising due to the natural increase in population and improvement of the standard of living, new wells with additional water abstractions for non agricultural purposes that affected the aflaj system, beside the rainfall pattern where the average rainfall has decreased in the last few years. Water shortage caused the abandonment of some farms and believed to has some effects on the soil The limitation of the existing water supply facilities is believed to have some effects restricting population growth. Shortage of water, which occurred occasionally, forced people to ration their water provisions, to obtain water from distant sources, or migrate to other villages or to abandon their settlements
Rainwater Harvesting in Jabal Al-Akhdar Different Studies on Possible Solutions To support the locals in the mountainous areas and to provide a sufficient basis that allows them to continue their traditional way of life with respect and retain of the social structure of settlements, while profiting from modern achievements, the government had made great efforts to study the best ways and techniques. Hence, many studies were carried out in the area to study the situation and possible solutions for solving water resources shortage problems The Main Studies that were carried out can be briefed below: In 1989 a reconnaissance survey and study of water resources in the Jabla Akhdar was carried, Development of Water Resources for Agricultural Use in Jabal Akhdar. The report identifies a number of ways in which the water supply facilities of region could be improved. In 1990, a study was carried out, Jebal Akhdar, 64 Hydraulic Structures. The study aimed to evaluate the potential for improving the water supply resources of a number of settlements, principally in the higher reaches of the Jabal Akhdar, for which retention dams were listed as the preferred option.
Rainwater Harvesting in Jabal Al-Akhdar Different Studies on Possible Solutions In 1999, The Ministry carried out s Feasibility Study for Flood water Harvesting Techniques in Oman to: –Identify, study, evaluate, rank, and recommend suitable sites of disused quarry pits as recharge pits and sites for other flood water harvesting techniques suitable in Oman. Eight water assessment regions were comprised –Spate irrigation system were also studied –Injection wells, recharge shafts were also suggested with recommendation of further studies –Economic analysis, Socio-economic and environmental aspects, operation and maintenance aspects, and ranking and prioritization of quarry pits, were all considered in this study The study concluded that 11 quarry out of the 45 that were studied were considered as viable recharge pits (infiltration ponds) in Oman
Rainwater Harvesting in Jabal Al-Akhdar Possible Solutions The survey and studies indicated that the most efficient way for water augmentation is the construction of retention dams for the following reasons: –Artificial recharge is not feasible in the higher reaches of Al-Jabal Al-Akhdar due to the non existence of suitable aquifer –Natural groundwater storage and transport occurs mainly in rock fractures and this source of already used by the traditional water supply systems such as aflaj –Only retention dams were found to be not affecting adversely the existing water supply systems –It is a traditional and well known method in Jabal Al-Akhdar and therefore, fully accepted by the villagers without unwanted social impacts on the communities –Agricultural villages can use the natural stored water for irrigation through aflaj system and the stored water by the retention dams for domestic use, livestock, and expanding agriculture activities –The stored surface water allows for preserving the high quality spring water for drinking purposes only which will help in counteract the trend of increasing well abstraction
Rainwater Harvesting in Jabal Al-Akhdar Construction of Small Storage Dams As a results of the above mentioned water resources situation in Jabal Al- Akhdar, fifty small storage dams were constructed in Al Jabal Al-Akhdar to provide and develop water resources of village occupants and population spread near wadi channels, and remote mountain areas which suffer from lack of water resources. The project comprised the storage dams, pipelines to the villages and farms, and small service reservoirs or water tanks Local material were used when ever is possible, using donkeys to transport them to the site, otherwise helicopters were used to transport the material as only few sites have been accessible by vehicles.
Rainwater Harvesting in Jabal Al-Akhdar Small Storage Dams
Rainwater Harvesting in other Remote Areas The success of the construction of small dams in Jabal Al-Akhdar let to construct similar small surface storage dams in different areas of the Sultanate to provide water for agricultural and livestock use. A total of 90 small dams were constructed in Oman with a total capacity of (137.9) Million m 3 ; –6 dams in Jabal Kor –5 dams in Jabla Surat –4 in Dhofar Governorate –2 in Jabal Al-Abyadh –3 in the mountainous areas in Ibri –3 in Rustaq
Wadi Dayqah Dam : The largest concrete storage dam in the Arabian peninsula. The maximum storage capacity of this dam is 100 Million m 3. The expected yearly yield is in the order of 35 Million m 3 to augment priority domestic supply in the Capital Area (20 Million m 3 /year) and to provide the Wilayat of Qurayat with both domestic and irrigation water supplies (15 Million m 3 /year). Other Storage Dams
Other Rainwater Harvesting Techniques Birkats or Cisterns: it is a traditional system of water harvesting that is designed to collect and store rainfall – generated flows. It comprises an excavated chamber or naturally occurring hallow structure. For centuries the utilization of birkats has been vital for the survivals and development of many remote settlements in the Musandam peninsula where they serve as the only source of water to meet domestic and livestock requirements. The government decided to maintain the cisterns as they are important in enhancing the water resources in Musandam. An inventory of these cisterns was undertaken in Musandam Governorate with a view to establishing location, assessing structure status and water use, and determining maintenance requirements together with estimated cost. A total of 967 cisterns were located, where 80% were found operational. The Government decided to aid in maintaining theses cisterns through providing the required materials to the owners of these cisterns About 147 cisterns were maintained in Bukha, 225 in Daba, and 595 in Khasab, were maintained in the last few years.
Other Rainwater Harvesting Techniques Birkats or Cisterns
Water Demand Management Water-demand management consists of all activities to increase efficiency in water supply and water usage and promote water recycling. Incentives will be given to agricultural activities using modern irrigation systems, industries that practice water reuse since they contribute directly to water-demand management and to the reduction of effluents. New housing, commercial and industrial estates shall be fitted with water- saving devices, including rainwater harvesting devices. In order to insure the success of water demand management strategy in Oman three major projects aiming at the evaluation of water use and the development of water resources database in Oman were undertaken. These are: The national well inventory project: The Aflaj inventory project: The hydrogeological maps project:
The Way Foreword in Water Resources Management The main issues to achieve these principles are: Balancing water uses to water availability Adopting improved irrigation techniques and selecting appropriate crops to reduce agricultural water use Managing water resources effectively and efficiently Increasing the use of treated wastewater and desalinated water Minimizing water pollution, flood damages and drought consequences Provision of sufficient water to spur and sustain economic Provision of access to safe, adequate and affordable water supply, hygiene and sanitation Protecting the groundwater resources in qualitative and quantitative terms Creating and cultivating conservation awareness; Establishing an integrated program for the conservation and management of the resources at basin level Controlling saline intrusion by reducing abstraction below the long-term recharge Controlling urban water losses Using Rainwater harvesting techqniques for remote areas when ever possible